In many situations, tissue may need to be accessed at a remote surgical site, excised from the adjacent anatomy and then the excised tissue removed from the remote surgical site. By way of example but not limitation, during arthroscopic surgery, endoscopic surgery, ENT surgery, etc., relatively small visualization devices (e.g., “scopes”) and relatively small surgical tools (e.g., graspers, cutters, cauterizers, etc.) may be introduced into a restricted portion of the human body (e.g., the interior of a joint, the interior of the abdomen, the interior of a nasal passage, etc.) and then used at that location for a specific surgical procedure (e.g., to trim meniscal cartilage in a joint, to excise a tissue mass in the abdomen, to excise a tissue mass in a nasal passage, etc.).
In many such surgeries, fluid may be introduced into the surgical site (and thereafter removed from the surgical site) so as to distend the anatomy for better access and/or visualization (e.g., so as to distend the knee joint for better access and/or visualization), and/or to improve visibility (e.g., so as to flush away blood), and/or to remove debris (e.g., so as to remove severed tissue by suction.)
One of the surgical tools frequently employed in such surgeries is the so-called “powered shaver”. Powered shavers typically comprise an outer tube having a window, and an inner tube rotatably disposed within the outer tube and having an opening, wherein rotation of the inner tube within the outer tube causes the opening of the inner tube to repetitively sweep across the window of the outer tube, whereby to shear off tissue extending into the window of the outer tube and the opening of the inner tube. Suction is typically applied to the interior of the inner tube so as to remove the tissue sheared off by the powered shaver.
Ideally, in addition to providing the aforementioned cutting action, the powered shaver is also able to provide either irrigation or suction to the remote surgical site, as desired by the surgeon, or to simultaneously provide both irrigation and suction to the remote surgical site.
In one construction, irrigation fluid is supplied to the gap between the interior of the outer tube and the exterior of the inner tube so that the irrigation fluid can be used to distend the anatomy and/or flush away blood and/or debris, and the irrigation fluid (and/or blood and/or debris) is removed from the surgical site by suction which is applied to the interior of the inner tube. In this way, the powered shaver is able to provide irrigation, cutting and suction in a single device.
Unfortunately, in many situations it may be desirable to form the powered shaver with a curved (i.e., non-linear) configuration. In this situation, the inner tube must be flexible in order to allow the inner tube to rotate about a curved axis (i.e., the curved axis of the outer tube), but must also be able to transmit torque along its length so as to enable cutting.
One approach for forming a flexible, torque-transmitting inner tube for the powered shaver is to form the inner tube with a plurality of slits extending through the side wall of the inner tube—these slits enable the inner tube to flex as it rotates about a curved axis while still allowing torque to be transmitted along the length of the inner tube.
Unfortunately, providing slits in the inner tube of a powered shaver is problematic where irrigation fluid is to be supplied to the surgical site through the gap between the interior of the outer tube and the exterior of the inner tube, and where suction is to be applied to the surgical site through the interior of the inner tube, since the slits in the inner tube effectively create a “short circuit” between the irrigation and suction lines, thereby undermining the irrigation and suction functions. Therefore, it can be problematic to provide a powered shaver which can provide irrigation, cutting and suction in a single device, and which has a curved (i.e., non-linear configuration).
Also, in situations where suction is to be applied to the surgical site through the interior of the inner tube without supplying irrigation fluid to the surgical site through the gap between the interior of the outer tube and the exterior of the inner tube, the provision of slits in the inner tube may compromise suction effectiveness at the surgical site (i.e., the suction force at the distal end of the inner tube is reduced since the slits in the inner tube allow the suction source to pull through the wall of the inner tube from the gap between the interior of the outer tube and the exterior of the inner tube).
A similar problem occurs where irrigation fluid is to be applied to the surgical site through the interior of the inner tube without applying suction to the gap between the interior of the outer tube and the exterior of the inner tube.
Thus it would be advantageous to provide a new powered shaver which is able to provide, either independently or simultaneously, irrigation, cutting and/or suction in a single device, and which may have a curved (i.e., non-linear) configuration. Furthermore, it would be advantageous to provide a new powered shaver which may have a curved (i.e., non-linear) configuration, wherein the new powered shaver comprises an outer tube and an inner tube rotatably disposed within the outer tube, with the lumen of the inner tube being fluidically sealed from the gap between the exterior of the inner tube and the interior of the outer tube.